The epilepsies comprise a common and devastating collection of disorders that affect about 1% of the U.S. population. This study is aimed at identifying one or more mutant genes that predispose individuals to juvenile myoclonic epilepsy and related forms of idiopathic generalized epilepsies. Large pedigrees are being identified throughout India in which there are at least four affected persons. Detailed history, neurological examination and EEG are being obtained and DNA isolated to perform a genomic screen for linkage/association analysis. Both model-based likelihood analyses and model-free analyses will be performed in order to better define the disease as a genetic entity and to determine chromosomal locations of the genes involved.